An ever-increasing number of applications (i.e., computer software) with various features are available to users of computers. Users can tailor the operation of these applications to suit their needs by specifying various configuration parameters. For example, a browser application may have a configuration parameter that provides a URL of a web page that is displayed initially whenever the browser application starts (i.e., “a home page”). The browser application may also have configuration parameters that identify programs to be invoked to process certain types of content (e.g., a “jpeg” file) and that specify passwords to be used when the application connects to various servers. The values of the configuration parameters can be stored in application-specific configuration files such as UNIX resource files or in a central registry such as the Windows® registry files. The application-specific configuration file for an application may have an internal format that is specific to that application. With a central registry, many different applications can share the same configuration parameters. The applications access these files to retrieve the values of their configuration parameters.
If certain configuration parameters have incorrect values, then the applications may exhibit an undesired behavior. For example, if the value of a home page configuration parameter is not set correctly, then when the browser application starts, it will exhibit an undesired behavior by not displaying a home page or displaying the wrong home page. If a configuration parameter incorrectly indicates a certain text editor should be invoked to process a graphics file, then the undesired behavior will be the incorrect display of the graphics content.
The configuration of a computer system may also refer to the files that are installed on that computer system. For example, when an application is installed on a computer system, the application may install various auxiliary files, such as dynamic link libraries, that are needed for proper operation of that application. If one of the auxiliary files is modified or removed from the computer system, then the application may not operate properly. The removing or replacing of auxiliary files is especially problematic when a later-installed application uses a different version of an auxiliary file. When the later-installed application is installed, it may replace the version of an auxiliary file used by an earlier-installed application, which may cause of the earlier-installed application to operate incorrectly.
The use of the correct configuration is particularly important to servers that provide services to many client computers. If a server has an incorrect configuration, then the server may not be able to provide its service to its clients, which may number in the hundreds. The inability of the clients to use the services of the server may also result in the failure of those clients. Thus, an incorrect configuration may not only cause a server to fail but may also cause each of the clients that depend on that server to fail.
Because of the complexity of applications and their large number of configuration settings (e.g., configuration parameters and auxiliary files), it can be very time-consuming to troubleshoot which configuration settings are at fault for causing an application to exhibit the undesired behavior. Most users of computers, including information technology personnel, have difficulty performing this troubleshooting. As a result, users typically rely on very experienced technical support personnel to assist in the troubleshooting. This troubleshooting not only is expensive but also users may experience a significant productivity loss as a result of their inability to effectively use an application that is exhibiting an undesired behavior, especially when the application is executed by a server and the users of its clients cannot use the application.
Typically, technical support personnel use an ad hoc approach to troubleshooting configuration problems. Because some central registries store over 200,000 configuration parameters and some applications rely on hundreds of auxiliary files, the personnel using knowledge gained from experiencing similar problems will try to narrow in on the at-fault configuration setting. This ad hoc approach can take a considerable amount of time and even longer if it is a combination of configuration settings that is incorrect.